It is true that in industrialized countries, the environment is one of the main concerns. The central part of the human body (also called the core) is "homeothermic" its temperature remains constant at 37°C and varies very little according to the external temperature [ω7]. To maintain the temperature of the central core, the human body is in a permanent thermodynamic exchange, there is a permanent balance between heat input and output.
So if the body's temperature is lower than that of the surroundings, the body receives heat from the outside, otherwise the body loses it. The brain, mainly through the hypothalamus, compares the set temperature in the central nucleus with the body temperature. Note: the sensation of cold varies depending on the wind speed in the environment where the subject is located.
The mechanism is through the evaporation of the amount of water secreted in the skin through sweat. However, the notion of thermal comfort is not limited to a temperature level, it is a function of ventilation (and therefore wind speed), metabolism and the geographical location of the home. As we have seen in the previous paragraphs, the regulation of the temperature of the vital organs of the human body is carried out by the Hypothalamus.
The temperature of the air inside the room - The radiation of the walls that form the room - The relative humidity (hygrometry) in the room.
The Electromagnetic Spectrum
Absorption Factor (α), Reflection Factor (ρ), Transmission Factor (τ)
It is the heat from a surface of a body transformed into an electromagnetic wave that propagates in the air and even the vacuum [4]. If ; the body is said to be opaque to radiation (no current passes through the body) If the body is said to be transparent to radiation. If some of the energy is absorbed, but this part is constant regardless of the wavelength of the incident energy, the body is said to be gray (otherwise it is said to be colored.
If the proportion of absorbed energy is independent of the angle of incidence of the received radiation, the body is called matte (otherwise it is said to be smooth).
The Notion of the Black Body, the Sun
The Generalized Heat Transfer
Ecoresponsible Thermal Study of a House a. The Thermal Balance
The thermal balance of the building aims to control the thermal comfort of its occupant. It is a mandatory part of the HVAC (Heating, Ventilation, Air Conditioning) study of a building, as well as any construction related to the control and regulation of internal temperature. Thermal contributions to the house are illustrated by the figure below (note that during summer, we fight against radiation (heat coming from outside); during winter, we fight against deperdiction (heat lost from inside).
It is an interactive heat balance calculation tool on Excel with programs under Visual Basic. We chose it because it is a professional tool that respects the norm and has a fairly affordable cost compared to other tools and software of the same kind. The selected climatic conditions of the area where the house is located - The thermal contributions of radiation.
Once the entries are made, the tool directly outputs the results by station and the total balance in watts. It is still necessary to check for possible irregularities before choosing the appropriate equipment for the thermal comfort of the house. In our approach, we do not limit ourselves to the choice of air-conditioning equipment, but to the way to limit the thermal loads that must be compensated and reduce losses.
Also, the logic of the design and choice of equipment is aimed at environmentally friendly solutions. GCT2: the use of thermal screens (blinds, awnings) - GCT3 the use of reinforced thermal insulation, - GCT4 the use of high inertia materials. GCT5 the use of natural convection - GCT6 the optimized use of the VMC, - GCT7: geocooling,.
Classification Criteria
Qualitative Indicators of Solutions
The Multi-Criteria Analysis Tool
Measurement Tools
Discussion
- Comparison of a Traditional and an Ordinary Housing Unit a. Presentation of the Models to be Simulated
- Geographic Location
- Models to be Simulated
- The Traditional House Model
- Basic Heat Balance
- Comparison of Room Temperatures
- Interior Temperature of the Traditional House
- Outside Temperature of the Traditional House (Temperature Taken at the Level of the North-West Façade at the Same Level of the Roof; Windows Facing North-West)
- Conclusion
- The Interior Temperature of the Basic Standard Box Model
- Outdoor Temperature at the Ordinary Basic House Model (Temperature Taken at the Southwest Façade at the Same Level as the Roof; Windows Facing Southwest)
- Conclusion
- Ranking of Adapted Eco-Responsible Solutions a. Case of the Traditional House
This simulation model is built to represent an ordinary house in the Malagasy population. It will be the subject of simulations for optimal solutions in terms of environmentally responsible comfort. The thermal comfort specifications take into account the six thermal comfort parameters as well as the thermal contributions through the envelopes induced by the operation of the room.
Occupancy rate: number of persons per room or per square meter of living area - Sensible thermal power: 68W per person; Latent heat input 34W per person (considering moderate physical activity). Glazed surfaces taken into account in the thermal calculation: insert (take into account: . geographical exposure, contribution of radiation through glazing, contribution of conduction through glazing). Wall surfaces (envelopes) taken into account in the thermal calculation: to be inserted (considered: geographical exposure, contribution of convection through the walls) - Surface of roofs (envelopes) taken into account in the thermal calculation: to be inserted (taken into account: solar energy) exposure, contribution by convection, contribution by radiation) - Air recovery loss: insert, we will take into account the conditions it specifies.
It can be confirmed that in terms of thermal comfort, a traditional house is more viable than the basic standard house for the Malagasy population. We note that the temperatures are not taken on the same days for the two models, instead what interests us is the delta between indoor and outdoor temperatures. Exterior temperature of the traditional house (temperature roof at the level of the northwest facade at the same level of the roof; windows to the northwest) the northwest facade at the same level of the roof; Windows to the northwest).
For the traditional home, we can confirm a difference in indoor and outdoor temperatures that is very close to what is recommended by the specifications. Outdoor temperature in the normal base house model (temperature measured at the southwestern facade at the same level as the roof; southwestern windows) the southwestern facade at the same level as the roof; south-west facing windows). The temperature difference between inside and outside is about 3.5°C, but the interior exceeds the temperature stated in the specifications by more than 3°C.
Comparison of suitable solutions for the two cases. The advantageous solutions are colored green. Comparison of eco-responsible suitable solutions for the models with two houses (Left: for the traditional house model, right: basic ordinary house model). Comparing the graphs of the adapted solutions, we notice that bioclimatic design, natural convection and geo-cooling play key roles in both cases.
We will have more of a tendency to insulation, so another analysis in this sense should follow this study in an optic of improving the thermal comfort of the usual basic house.
Conclusion
